EP0890775B1 - Locking device for connecting pipe members and use of such a connection - Google Patents

Abstract

The locking mechanism for a plain end (1) and socket (3) of two pipe sections (2, 4) comprises a crown (40) and a locking insert (42) connected to a hoop (43) of elastomer or similar material. The crown is designed to fit inside a locking chamber before the plain pipe end is inserted into it, while the insert is designed to expand radially inside the chamber and extend the locking ring so it goes over the plain pipe end. The locking ring has a connecting element (49) with a collar (55) which extends radially inwards beyond the outer surface (44) of the insert by over 0.4 mm or more than 4 per cent of the of the insert's main radial height.

Description

The present invention relates to a device for locking for the assembly of a plain end and a fitting of two pipe elements, device of the type comprising a locking crown which comprises at least one locking insert connected to a ring hooping in elastomer or the like, this crown being intended to be housed, pending, in a room integral locking of said front socket introduction of the plain end in this room, part connecting ring extending along a surface end of the insert intended to be oriented towards the axially outer end of the locking, the insert being intended, during the introduction of the plain end into the locking, to move radially outward in deforming the ring so that it comes place a radially surface around the plain end outer of the crown being intended to bear on an inclined reaction surface of the latch and insert having a surface radially interior with at least one relief is intended to rest on the surface radially exterior of the plain end to lock the assembly of the two pipe elements.

Such devices are used for the locking of pipe pipes. Several inserts are then regularly distributed angularly and are peripherally connected by the hoop ring. The locking chamber is made in the socket or in a locking counter flange fixed on nesting.

The inserts are provided on their surface radially inner teeth intended to come directly hang the outer surface of the plain end, to prevent, after joining two pipes, the withdrawal of the plain end out of the corresponding socket. In a known arrangement (EP-A-0 235 818), part of ring connection extends over the end face outside of each insert and connects the ring to a retaining collar, outside the chamber lock, intended to rest on a surface rear support integral with the socket.

This retaining collar allows to retain axially the locking ring during insertion of the plain end in the locking chamber, and so hold the crown between the surface radially exterior of the plain end and the reaction surface of the locking chamber.

When introduced into the locking, the end of the plain end abuts on the outer end face of the inserts, between the edge radially inside of this face and the edge radially inside of the connecting part matching ring.

The end of the plain end then pushes the edge radially inside the outer end face of the insert in the direction axially opposite to the force of restraint exerted by the collar on the insert, creating thus a couple of force which can cause the tilting of the insert, or even separation of the insert and the ring.

This phenomenon appears mainly in the case where the clearance between the socket and the plain end is small, especially when the two pipe elements have thick coatings.

This tilting can lead to a position unwanted insert, toothed surface not facing the surface radially outside of the plain end and therefore unable to fill its attachment role.

The invention aims to solve the problem set out above by providing a device for locking which allows, in a simple and economical, to avoid a bad positioning, when penetration of the plain end into the locking, crown locking insert placed on standby in the locking chamber.

To this end, the subject of the invention is a locking device of the aforementioned type, characterized in that said connecting part of the ring is extends radially inwards by a bead boarding the end of the plain end, this boarding bead protrude radially inward beyond a radially inner edge of said outer end surface of the insert.

• ledit bourrelet d'abordage dépasse radialement vers l'intérieur du bord radialement intérieur de la surface d'extrémité extérieure de l'insert d'une distance h qui est supérieure à 0,4 mm,
• ledit bourrelet d'abordage dépasse radialement vers l'intérieur du bord radialement intérieur de la surface d'extrémité extérieure de l'insert, d'une distance h qui est supérieure à 4% de la hauteur radiale moyenne de l'insert,
• ledit bourrelet d'abordage dépasse radialement vers l'intérieur du bord radialement intérieur de la surface d'extrémité extérieure de l'insert, d'une distance h qui est supérieure à 3% du déplacement radial moyen de la bague lorsqu'elle vient se placer autour du bout uni,
• ladite surface d'extrémité extérieure de l'insert se prolonge radialement vers l'intérieur par une zone de jonction arrondie et/ou chanfreinée,
• ledit bourrelet d'abordage de la bague recouvre au moins partiellement la zone de jonction,
• ledit bourrelet d'abordage de la bague est prolongé axialement vers l'intérieur le long d'au moins une partie de la surface radialement intérieure de l'insert,
• le dispositif comprend une partie de retenue axiale destinée à prendre appui sur une surface d'appui arrière solidaire de l'emboítement, pour limiter les déplacements axiaux de la couronne lors de l'introduction du bout uni dans l'emboítement,
• la couronne de blocage comprend une partie formant une garniture d'étanchéité pour assurer l'étanchéité entre les deux éléments de canalisation assemblés, et
• ledit corps d'étanchéité est destiné à venir en appui au moins partiellement contre une collerette radialement intérieure de l'emboítement.

According to particular embodiments, the device can include one or more of the following characteristics:

• said collision bead protrudes radially inward from the radially inner edge of the outer end surface of the insert by a distance h which is greater than 0.4 mm,
• said collision bead protrudes radially inward from the radially inner edge of the outer end surface of the insert, by a distance h which is greater than 4% of the average radial height of the insert,
• said collision bead protrudes radially inward from the radially inner edge of the outer end surface of the insert, by a distance h which is greater than 3% of the mean radial displacement of the ring when it comes place around the plain end,
• said outer end surface of the insert is extended radially inward by a rounded and / or chamfered junction zone,
• said contact flange of the ring at least partially covers the junction zone,
• said contact flange of the ring is extended axially inwards along at least part of the radially inner surface of the insert,
• the device comprises an axial retaining part intended to bear on a rear bearing surface integral with the socket, in order to limit the axial displacements of the crown when the plain end is introduced into the socket,
• the locking ring comprises a part forming a seal to seal between the two assembled pipe elements, and
• said sealing body is intended to bear at least partially against a radially inner flange of the socket.

The invention also relates to an assembly pipe elements, in particular pipes, comprising a plain end of a first element of pipe inserted into a socket of a second channel element, the second element of pipeline also including a integral locking of the socket, said chamber being formed in the socket or in a counter flange fixed thereon, characterized in that it comprises a locking device as described above including the locking crown is housed in said chamber, a radially surface outer crown resting on a surface inclined reaction chamber of the locking chamber, and the radially inner surface of the insert bearing on the radially outer surface of the plain end in locking the assembly of the two elements of pipe.

In one embodiment, the assembly includes a radial compression packing interposed between the plain end and the socket.

• la figure 1 est une demi-vue en coupe longitudinale, avant assemblage, d'un bout uni d'un premier tuyau de canalisation et d'un emboítement d'un deuxième tuyau de canalisation muni d'un dispositif de verrouillage selon l'invention, cette vue étant prise dans un plan diamétral passant par un insert de blocage du dispositif de verrouillage,
• la figure 2 est une vue agrandie de la zone cerclée II de la figure 1,
• la figure 3 est une vue analogue à la vue de la figure 2, illustrant une variante du mode de réalisation de la figure 1,
• les figures 4 et 5 sont des vues analogues à la figure 2 illustrant respectivement un deuxième mode de réalisation de l'invention et une de ses variantes, et
• la figure 6 est une vue analogue à la figure 1 illustrant un troisième mode de réalisation de l'invention après assemblage des deux éléments de canalisation.

The invention will be better understood on reading the description which follows, given solely by way of example, and made with reference to the appended drawings in which:

• Figure 1 is a half view in longitudinal section, before assembly, of a plain end of a first pipe and a socket of a second pipe fitted with a locking device according to the invention , this view being taken in a diametral plane passing through a blocking insert of the locking device,
• FIG. 2 is an enlarged view of the circled area II of FIG. 1,
• FIG. 3 is a view similar to the view in FIG. 2, illustrating a variant of the embodiment of FIG. 1,
• FIGS. 4 and 5 are views similar to FIG. 2 respectively illustrating a second embodiment of the invention and one of its variants, and
• Figure 6 is a view similar to Figure 1 illustrating a third embodiment of the invention after assembly of the two pipe elements.

FIG. 1 shows a plain end 1, or male end, a first pipe 2 and a socket 3, or female end, of a second pipe line 4, ready to be assembled. The plain end 1 and the socket 3 are arranged substantially coaxially.

These pipes may in particular be pipes successive pipes, especially cast iron ductile, each pipe having a plain end 1 to a end and a socket 3 at another end.

The plain end 1 has a radially surface cylindrical outer 5 connected by a surface converging 6 at the edge 7 of the front end 8 of the plain end 1.

Internally, the socket 3 has successively a tapered entry surface convergent 9, a cylindrical surface 10 for guiding the plain end, an annular groove 11, an annular boss 12 and finally a sealing chamber 13 partially shown in Figure 1.

An annular seal 14 to radial compression, of axis coincident with the axis of the pipe 4 has an annular axial retaining heel 15 housed in the groove 11. This heel 15 is extended axially towards the interior of socket 3 (on the right in Figure 1) by a sealing body 16 housed in the chamber 13.

Externally, the socket 3 has since its entrance, located at its rear end 17, a flange 18 projecting radially, followed by a surface strongly convergent 19 connected to the outer surface current 20 of socket 3.

A locking counter flange 21 is fixed thanks to fixing bolts 22 (of which only one is shown in Figure 1) on the socket 3, to the rear end 17 thereof.

This counter flange 21 includes a part substantially frustoconical 23, arranged coaxially with socket 3 and extended radially outwards by a veil 24. This veil 24 is terminated by a flange peripheral 25 extending axially beyond the front end edge 26 of the counter flange 21. This end edge 26 is supported on edge 27 of the rear end 17 of the socket 3.

The veil 24 is pierced with holes 28 regularly angularly distributed, in which pass freely screws 29 of bolts 22. These screws 29 include each a threaded end 30 and an end 31 provided with an eccentric heel 32 bearing on the surface 19 of socket 3.

A nut 33 is screwed onto the end 30 of each screw 29 and rests on the rear surface 34 of the sail 24.

The bolts 22 thus ensure the connection of the counter-flange 21 and the socket 3.

Part 23 of counter flange 21 has internally a reaction surface 35 substantially spherical and converging towards the rear end 36 of the counter flange 21.

At the front end 26 of the counter flange 21, this surface 35 has a substantially radial opening larger than the radial opening of the surface input 9 of socket 3. Surface 35 delimits internally a locking chamber 37.

The rear end of part 23 has a radial outer support surface 38.

The counter flange 21 is provided with a device for lock 39 including a locking ring 40 housed pending in the locking chamber 37, and a retaining collar 41 located outside the chamber 37 and bearing on the surface 38.

Crown 40 includes locking inserts 42 metallic, regularly distributed angularly and linked together by a hoop ring 43 in elastomer.

These inserts 42 are blocks having a substantially trapezoidal longitudinal section with a small rear or outer face that is substantially radial 44 (figure 2), a large front or interior face substantially radial with a transverse groove, a radially inner surface 45 provided with teeth attachment 46, and a radially outer surface which converges towards the rear end 36 of the counterflange 21.

The rear faces 44 of the inserts 42 are oriented towards the front end 8 of the plain end 3, and towards the axially outer end of the chamber 37.

The ring 43 includes a veil radially exterior 47 peripherally connecting the surfaces radially outer inserts 42. This veil 47 is extended, towards the front end of the counter flange, by a substantially radial part 48 running along the front face of each insert 42, this part 48 being provided with a annular boss projecting rearward and housed in the groove of the front face of each insert 42.

The veil 47 is extended towards the rear by a radial connection part 49 (FIG. 2) extending along the face 44 of each insert 42. This part 49 is extended axially backwards, and up to the outside of chamber 37, by a junction segment tapered 50, flared outwards and terminated by a radial part 51 in which a ring is housed metallic 52. This radial part 51 forms the collar retainer 41.

The inserts 42 are intended, during the introduction of the plain end 1 into the chamber 37, at move axially forward and away radially outward by deforming the ring 43 so that it comes to be placed around the end uni 1. The collar 41 ensures the axial retention of the crown 40 during this introduction, keeping thus, on the one hand, the veil 47 in the vicinity of the surface of reaction 35, and on the other hand the surface 45 of each insert 42 in contact with the surface radially exterior of the plain end 1. Thus, after introduction complete with plain end 1 in socket 3, crown 40 is compressed radially on the surface 5. When a dislocation effort is exerted on the plain end, under the effect of the pressurization of the pipeline, the veil 47 abuts against the reaction surface 35, and the teeth 46 of the inserts bite the surface 5 in preventing the plain end 1 from withdrawing from the socket 3.

As can be seen in Figure 2, the face 44 of insert 42 ends with a radially edge interior 53 which is connected to the face radially interior 45 by a chamfered junction zone 54.

The connecting part 49 of the ring 43 extends radially inwards beyond the radially inner edge 53 of the face 44 of the insert 42 by a collision bead 55. This bead 55 extends radially towards the interior, cantilevered, beyond edge 53 over a distance h .

The radially inner surface 56 of the bead 55 converges forward and extends the face internal of segment 50.

When introducing the plain end 1 into the locking chamber 37, the front end 8 of the end uni 3 abuts against the bead 55. The surface 56 of this bead 55 slides successively on the surfaces 6 and 5 of the plain end 3 while the junction segment 50 moves aside and the plain end 1 progressively advances in the locking chamber 37.

Thanks to this characteristic, the face 44 of the inserts cannot abut directly against the end front 8 of the plain end 3, which avoids the risk of tilting of the inserts 42 mentioned above.

So that the bead 55 correctly fulfills its role of abutment, in particular when the segment 50 deviates, the distance h is greater than 0.4 mm and / or greater than 4% of the average radial height of the inserts 42 and / or greater at 3% of the average radial displacement of the ring 43 when the crown 40 is placed around the plain end 1.

The bead 55 extends radially inwards beyond the rear edge 57 of the surface 45 of each insert 42.

It is understood that the crown 40 of the device lock 39 can be accommodated in a locking provided in a counter flange, such as shown in Figure 1, or in a locking provided directly in the socket 3, for example between the entrance to the socket and the bedroom sealing of it.

In a variant shown in Figure 3, the collision bead 55 extends axially towards the front (so towards the inside of the pipe 4) by covering substantially the junction zone 54 and part of the radially inner surface 45 of the insert 42.

In this variant, the surface radially interior 56 of the bead 55 also extends towards the front, beyond the junction zone 54, and comes partially cover the radially inner surface 45 of insert 42.

Figure 4 illustrates another embodiment of the invention, which differs from the first mode of realization that the locking device does not includes no retaining collar 41 and therefore no junction segment 50 between it and the crown of blocking 40.

The usual behavior of such a device is distinguishes from the behavior of the device from the mode of previous achievement by the following.

When introducing the plain end 1 into the locking chamber 37, this moves the crown 40 axially, the crown 40 then being brought back elastically by retaining means (not shown) which push the crown 40 axially backwards, said retaining means being disposed between said crown 40 and the rear edge 27 of the pipe on which they rely on. These retaining means ensure then the axial retention of the crown 40 ensured by the collar 41 in the previous embodiment, then the plain end enters between the inserts and spreads the crown 40 to cross it.

In this embodiment, the connecting part 49 also extends radially inward beyond from edge 53 into a collision bead 55. The surface radially inner 56 of the collision bead 55 is also converging forward.

This characteristic allows, analogously in the previous embodiment, to avoid tilting inserts 42 when subjected to a force of axial penetration of the plain end 1 and the opposite force of detention.

FIG. 5 illustrates a variant of the mode of embodiment of FIG. 4 in which, in a way analogous to the variant of FIG. 3, the bead board 55 extends axially inwardly covering the junction zone 54 of the insert 42 and a part of the radially inner surface 45 of insert 42.

Figure 6 illustrates another mode of realization, in which the socket 3 has internally, successively, an entry surface convergent 9, a cylindrical guide surface 10, a locking and sealing chamber 58 and a inner flange 59. The sealing chamber 58 has a substantially cylindrical interior surface 60 which extends towards the rear by a surface of inclined reaction 61.

The crown 40 of the locking device is distinguished from the crown of the device of FIG. 4 only in that the front face and the wall 47 of the ring 43 are extended forward by a body sealing ring 62 with radial compression, this body 62 coming to bear at least partially against the flange 59. This figure also illustrates the relative positions after assembly of the plain end 1, of the socket 3 and the locking device 39.

In this embodiment, on the one hand the body seal 62 cooperates with the surface 5 of the plain end 1 and the opposite cylindrical surface 60 of the chamber 58 to seal the connection between the two pipes 2 and 4, and on the other hand the surface 45 of each insert 42 cooperates with the surface 5 of the plain end and the web 47 of ring 43 cooperates with the surface of reaction 61 of chamber 58 to ensure locking between the two pipes 2 and 4. In this case, when penetration of the plain end, it is the elasticity generated by the axial compression of the body 62 against the flange 59, which provides the axial retaining force of the device locking 39 allowing the spacing of the inserts 42.

Claims (12)

1. Locking device for the joint between a smooth end (1) and a socket (3) of two pipeline elements (2, 4), of the type comprising a blocking crown (40) which includes at least one blocking insert (42) joined to a binding ring (43) made of elastomer or the like, this crown (40) being lodged in readiness in a locking chamber (37; 58) integral with the said socket before introduction of the smooth end into this chamber, a connecting part (49) of the ring extending along an outer extremity surface (44) of the insert oriented towards the axially outer extremity of the locking chamber, the insert (42) being intended, upon the introduction of the smooth end (1) into the locking chamber (37; 58), to move apart radially outwards, thereby deforming the ring (43) such that the latter is placed around the smooth end, a radially outer surface of the crown being intended to bear on an inclined reaction surface (35; 61) of the locking chamber and the insert (42) having a radially inner surface (45), of which at least one catching relief (46) is intended to bear on the radially outer surface (5) of the smooth end (1) to lock the joint between the two pipeline elements (2, 4), characterized in that the said connecting part (49) of the ring (43) is continued radially inwards by a flange (55) for abutment of the extremity of the smooth end, this abutment flange (55) extending radially inwards beyond a radially inner edge (53) of the said outer extremity surface (44) of the insert.
2. Device according to Claim 1, characterized in that the abutment flange (55) extends radially inwards beyond the radially inner edge (53) of the outer extremity surface (44) of the insert by a distance h which is greater than 0.4 mm.
3. Device according to Claim 1 or 2, characterized in that the abutment flange (55) extends radially inwards beyond the radially inner edge (53) of the outer extremity surface (44) of the insert by a distance h which is greater than 4% of the mean radial height of the insert.
4. Device according, to any one of Claims 1 to 3, characterized in that the abutment flange (55) extends radially inwards beyond the radially inner edge (53) of the outer extremity surface of the insert by a distance h which is greater than 3% of the mean radial displacement of the ring when it is placed around the smooth end.
5. Device according to any one of Claims 1 to 4, characterized in that the said outer extremity surface (44) of the insert is joined to the radially inner surface (45) by a rounded and/or chamfered junction zone (54).
6. Device according to Claim 5, characterized in that the abutment flange (55) of the ring at least partially covers the junction zone (54).
7. Device according to any one of Claims 1 to 6, characterized in that the abutment flange (55) of the ring is continued axially inwards along at least a part of the radially inner surface (45) of the insert.
8. Device according to any one of Claims 1 to 7, characterized in that it comprises an axial retention part (41) intended to bear on a rear bearing surface (38) integral with the socket (3), to limit the axial displacements of the crown (40) upon the introduction of the smooth end (1) into the socket (3).
9. Device according to any one of Claims 1 to 8, characterized in that the blocking crown (40) comprises a radial-compression sealing body (62) to ensure the sealing between the two joined pipeline elements (2, 4).
10. Device according to Claim 9, characterized in that the said sealing body (62) is intended to come to bear at least partially against a radially inner collar (59) of the socket (3).
11. Joint between pipeline elements, especially pipes, comprising a smooth end (1) of a first pipeline element (2) introduced into a socket (3) of a second pipeline element (4), the second pipeline element (4) also comprising a locking chamber (37; 58) integral with the socket, the said chamber being formed in the socket or in a counterflange (21) fixed onto the latter, characterized in that it comprises a locking device according to any one of Claims 1 to 10 in which the blocking crown (40) is lodged in the said chamber, a radially outer surface of the crown bearing on an inclined reaction surface (35; 61) of the locking chamber, and the radially inner surface (45) of the insert (42) bearing on the radially outer surface (5) of the smooth end (1), thereby locking the joint between the two pipeline elements (2, 4).
12. Joint according to Claim 11, characterized in that it comprises a radial-compression packing (14; 62) interposed between the smooth end (1) and the socket (3).

Images